Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
December proves to be the coldest month, recording an average maximum temperature of 29.3°F (-1.5°C) and a minimum temperature of 18.7°F (-7.4°C).Humidity
In December, the average relative humidity is 91%.Rainfall
The month with the most rainfall in Heron is December, when the rain falls for 11.2 days and typically aggregates up to 3.66" (93mm) of precipitation.Snowfall
Months with snowfall are January through May, September through December. In December, it is snowing for 19.5 days. Throughout December, 15.31" (389mm) of snow is accumulated. Throughout the year, there are 80.8 snowfall days, and 60" (1524mm) of snow is accumulated.Daylight
With an average of 8h and 24min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 8:13 am and sunset at 4:52 pm. On the last day of December, sunrise is at 8:33 am and sunset at 5:00 pm MST.
Sunshine
The average sunshine in December is 3.3h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 1. A UV Index value of 2, and less, symbolizes a minimal health vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: The daily high UV index of 1 during December translates into the following recommendations:
Though extended exposure to the sun typically does not concern most people, it is crucial to always shield children, infants, and those with sensitive skin. Direct Sun exposure should be minimized especially during midday when radiation is most intense. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses. Remember to consider! The UV radiation from the Sun can be intensified nearly twice by the reflection of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the coldest month?
How cold is it in December?
What is the average humidity in December?
What is the rainiest month?
How much does it rain in December?
How much does it snow in December?
What is the month with the shortest days?
How many hours of daylight does Heron have in December?
When are sunrise and sunset in December in Heron?
How long on average sun shines in December?
What are the months with the lowest UV index?
How high is the UV index in December?
Average temperature in December
Heron, MT
- Average high temperature in December: 29.3°F
The warmest month (with the highest average high temperature) is August (78.3°F).
The month with the lowest average high temperature is December (29.3°F).
- Average low temperature in December: 18.7°F
The month with the highest average low temperature is August (49.1°F).
The coldest month (with the lowest average low temperature) is December (18.7°F).
Average pressure in December
Heron, MT
- Average pressure in December: 30.18"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The months with the lowest atmospheric pressure are June and August (29.92"Hg).
Average wind speed in December
Heron, MT
- Average wind speed in December: 3.5mph
The windiest month (with the highest average wind speed) is April (4.5mph).
The calmest month (with the lowest average wind speed) is December (3.5mph).
Average humidity in December
Heron, MT
- Average humidity in December: 91%
The month with the highest relative humidity is January (94%).
The month with the lowest relative humidity is August (52%).
Average rainfall in December
Heron, MT
- Average rainfall in December: 3.66"
The wettest month (with the highest rainfall) is December (3.66").
The driest month (with the least rainfall) is August (0.55").
Average rainfall days in December
Heron, MT
- Average rainfall days in December: 11.2 days
The month with the highest number of rainy days is April (19.3 days).
The month with the least rainy days is August (6.9 days).
Average snowfall in December
Heron, MT
- Average snowfall in December: 15.31"
The month with the highest snowfall is January (15.87").
The months with the least snowfall are June, July and August (0").
Average snowfall days in December
Heron, MT
- Average snowfall days in December: 19.5 days
The month with the highest number of snowfall days is December (19.5 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in December /
Average sunshine in December
Heron, MT
- Average daylight in December: 8h and 2min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 24min).
- Average sunshine in December: 3h and 2min
The month with the most sunshine is August (Average sunshine: 11h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 12min).
Average sunshine days in December
Heron, MT
- Average sunshine days in December: 8.4 days
The month with the most sunshine days is July (20.9 days).
The month with the least sunshine days is March (7.1 days).
Average UV index in December
Heron, MT
- Average UV index in December: 1
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 1).
Average cloud cover in December
Heron, MT
- Average cloud cover in December: 66
The month with the most cloud cover is January (Cloud cover 67).
The month with the least cloud cover is August (Cloud cover 14).
Average visibility in December
Heron, MT
- Average visibility in December: 3mi
The months with the highest visibility are May, June, July, August and September (6mi).
The months with the lowest visibility are January, February and December (3mi).
Heron, Montana, USA
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